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21.
In this article, the effect of ionization on the energy spectrum of electrons within the interaction of a laser pulse with hydrogen atoms is investigated using particle-in-cell simulation codes. The results show that the behaviour of electrons' energy distribution function in the field-ionized plasma, which occurred due to the field ionization, compared with that in the pre-plasma strongly depends on the pulse shape. For short rise-time pulses (here 30 fs), due to the rapid enhancement of laser electric field, ionization occurs quickly, and as a result, there is not much difference in the electron energy in both the media. However, for pulses with rise time of 40 fs, in the pre-plasma state, the electron population reaches higher energies compared with the field-ionized plasma state. The main reason for this difference is the nonlinear wave breaking that happens earlier due to density inhomogeneity in the field-ionized plasma. On the other hand, at longer rise-time pulses (here 60 and 70 fs), electrons achieve higher energies in the field-ionized plasma than those in the case of pre-plasma. In this case, because of density fluctuations in the field-ionized plasma, the Raman backscattered radiations are seeded by a strong initial noise at the earlier times and the Mendonca condition for chaos threshold is met sooner. Therefore, the electrons gain more energy through the stochastic mechanism that is in agreement with chaotic nature of the motion. 相似文献
22.
Radiophysics and Quantum Electronics - This work is a review of recent results, which have been obtained within the framework of the mathematical theory of dynamical chaos and are related to the... 相似文献
23.
Kazei Z. A. Snegirev V. V. Stolyarenko M. S. 《Journal of Experimental and Theoretical Physics》2021,133(5):591-598
Journal of Experimental and Theoretical Physics - The structural (lattice metric) and elastic characteristics of ErBaCo4O7 + x cobaltites, which are subjected to different heat treatment and are... 相似文献
24.
Vysotskii S. L. Kozhevnikov A. V. Filimonov Yu. A. 《Physics of the Solid State》2021,63(10):1579-1583
Physics of the Solid State - The interference of excited and received by current antennae magnetoelastic waves counterpropagating in an yttrium iron garnet film is experimentally studied. It is... 相似文献
25.
Foundations of Computational Mathematics - We present a finite element variational integrator for compressible flows. The numerical scheme is derived by discretizing, in a structure-preserving way,... 相似文献
26.
Chong Saehwa Riley Brian J. Nienhuis Emily T. Lee Dongjin McCloy John S. 《Journal of chemical crystallography》2021,51(3):293-300
Journal of Chemical Crystallography - Four different rare-earth oxyapatites of Ca2RE8(SiO4)6O2 (RE?=?Pr, Tb, Ho, Tm) were synthesized using a solution-based method followed by drying,... 相似文献
27.
Boundary Value and Inverse Problems for Some Classes of Nonclassical Operator-Differential Equations
We consider the solvability of boundary value problems and some inverse problems for operator-differential equations of odd order which can be referred to as mixed type equations since the coefficient of the higher order time derivative can change sign. Studying the general classes of boundary value problems with nonlocal boundary conditions, we establish the existence and uniqueness theorems of regular solutions under some conditions on data.
相似文献28.
Analysis Mathematica - We introduce and study the k-Hankel Gabor transform. We investigate the localization operators for this transform. In particular, we study their trace class properties and we... 相似文献
29.
Siberian Mathematical Journal - Some structural properties are discussed of the functions in $ P_{2}\times P_{2} $ . We describe the properties of functions not belonging to the maximal... 相似文献
30.
Dobrokhotov S. Yu. Minenkov D. S. Nazaikinskii V. E. 《Theoretical and Mathematical Physics》2021,208(2):1018-1037
Theoretical and Mathematical Physics - We illustrate the construction and application of the Maslov canonical operator with examples of Bessel functions. For real values of the argument, we derive... 相似文献